Effects of cutting parameters on tool insert wear in end milling of titanium alloy Ti6Al4V

Titanium alloy is a kind of typical hard-to-cut material due to its low thermal conductivity and high strength at elevated temperatures, this contributes to the fast tool wear in the milling of titanium alloys. The influence of cutting conditions on tool wear has been focused on the turning process, and their influence on tool wear in milling process as well as the influence of tool wear on cutting force coefficients has not been investigated comprehensively. To fully understand the tool wear behavior in milling process with inserts, the influence of cutting parameters on tool wear in the milling of titanium alloys Ti6Al4V by using indexable cutters is investigated. The tool wear rate and trends under different feed per tooth, cutting speed, axial depth of cut and radial depth of cut are analyzed. The results show that the feed rate per tooth and the radial depth of cut have a large influence on tool wear in milling Ti6Al4V with coated insert. To reduce tool wear, cutting parameters for coated inserts under experimental cutting conditions are set as: feed rate per tooth less than 0.07 mm, radial depth of cut less than 1.0 mm, and cutting speed sets between 60 and 150 m/min. Investigation on the relationship between tool wear and cutting force coefficients shows that tangential edge constant increases with tool wear and cutter edge chipping can lead to a great variety of tangential cutting force coefficient. The proposed research provides the basic data for evaluating the machinability of milling Ti6Al4V alloy with coated inserts, and the recommend cutting parameters can be immediately applied in practical production.     

HIGH SPEED MILLING OF GRAPHITE ELECTRODE WITH ENDMILL OF SMALL DIAMETER

Graphite becomes the prevailing electrode material in electrical discharging machining (EDM)currently.Orthogonal cutting experiments are carried out to study the characteristics of graph- ite chip formation process.High speed milling experiments are conducted to study tool wear and cutting forces.The results show that depth of cut has great influence on graphite chip formation.The removal process of graphite in high speed milling is the mutual result of cutting and grinding process. Graphite is prone to cause severe abrasion wear to coated carbide endmills due to its high abrasive- ness nature.The major patterns of tool wear are flank wear,rake wear,micro-chipping and breakage. Cutting forces can be reduced by adoption of higher cutting speed,moderate feed per tooth,smaller radial and axial depths of cut,and up cutting.     

基于ABAQUS的钛合金铣削力的模拟分析

为了研究钛合金在铣削过程中切削力随着切削参数的变化规律,建立了三维斜角切削有限元模型。通过对材料本构模型,刀—屑接触摩擦模型和切屑分离准则等关键环节建模,采用通用有限元求解器ABAQUS/Ex-plicit对钛合金Ti6Al4V的斜角切削过程进行了模拟,获得了切削速度v、切削深度ap和每齿进给量fz对切削力的变化趋势及影响程度。模拟结果表明:切削力随着切削深度ap和每齿进给量fz的增大而增大,而随着切削速度增大切削力波动很小。切削深度对切削力的影响最大,进给量次之,切削速度对切削力的影响最小。该模型可以为切削参数的合理选择提供参考。     

黛杰在中国

<正>经过十余年的努力,黛杰产品在中国市场的知名度和销售量取得了傲人的成绩。日本黛杰工业株式会社于1938年成立,作为从原料粉末到成品产出一贯制专业硬质合金厂家,产品性能和品牌知名度一直深受广大用户的拥戴。从2002年开始,黛杰在中国上海设立代表处,专门针对中国客户提供售后服务。继2006年设立广东事务所后,2009、2010、2013年又分别在大连、武汉、成都设立联络处。此外,黛杰汉金(沧州)精密模具有限公司于2013年10月在河北省黄骅市正式运营投产。     

液氮冷却下大进给铣削TC4钛合金的试验研究

钛合金是现代飞行器的主要结构材料之一,是一种典型的难加工材料。针对切削加工钛合金时刀具磨损快、表面质量不易控制等难题,将TC4钛合金作为研究对象,以液氮作为冷却介质,进行了TC4钛合金的大进给铣削试验,测试了液氮冷却条件下大进给铣削TC4钛合金的铣削力、铣削温度以及刀具磨损等,并与乳化液和低温冷风条件下的测试结果进行了对比分析。结果表明:在以较大的切削速度和每齿进给量铣削TC4钛合金时,采用液氮冷却比使用乳化液能更有效地降低切削力和切削温度;比采用低温冷风冷却能更有效地延长刀具寿命。     

高速铣削钛合金Ti-6Al-4V切削力仿真研究

切削力对工件的机械加工性和刀具磨损有重要的影响。基于有限元仿真技术,针对钛合金Ti-6Al-4V高速铣削力进行数值仿真,重点研究切削参数对铣削力的影响规律。结果表明:随着每齿进给量和径向切深的增加,切削力有不同程度的增加;随着轴向切深的增加,切削力呈正比增加趋势,但主轴转速对铣削力影响并不明显。分析结果为钛合金Ti-6Al-4V高速铣削加工工艺参数优化奠定了基础。     

The effects of cutting parameters on tool life and wear mechanisms of CBN tool in high-speed face milling of hardened steel

High-speed face milling of AISI H13 hardened steel is conducted in order to investigate the effects of cutting parameters on tool life and wear mechanisms of the cubic boron nitride (CBN) tools. Cutting speeds ranging from 400 to 1,600 m/min are selected. For each cutting speed, the metal removal rate and axial depth of cut are fixed, and different combinations of radial depth of cut and feed per tooth are adopted. The tool life, tool wear progression, and tool wear mechanisms are analyzed for different combinations of cutting parameters. It is found that for most of the selected cutting speeds, the tool life increases with radial depth cut and then decreases. For each cutting speed, the CBN tool life can be enhanced by means of adopting suitable combination of cutting parameters. When the cutting speed increases, the normal wear stage becomes shorter and the tool wear rate grows larger. Because of the variations of cutting force and tool temperature, the tool wear mechanisms change with different combinations of cutting parameters even at the same cutting speed. At relatively low cutting speed, in order to acquire high tool life of the CBN tool, the tool material should possess sufficient capability of resisting adhesion from the workpiece. When relatively high cutting speed is adopted, retention of mechanical properties to high cutting temperature and resistance to mechanical impact are crucial for the enhancement of the CBN tool life.     

螺纹铣削切削力有限元分析及试验

为了研究螺纹铣削法加工钛合金螺纹时切削力随切削参数的变化规律,通过对材料本构关系、刀—屑接触及切屑分离准则进行分析,建立了能反映刀具自转、公转及轴向进给运动的三维螺纹铣削模型。利用该模型对每齿进给量和切削速度对切削力的影响进行分析,结果表明:切削力随每齿进给量的增大而增大,随切削速度增加而减小,且每齿进给量对切削力的影响较为显著。通过螺纹铣削试验对所建立的三维铣削模型进行验证,表明所建立模型的误差最大为14%,可满足实际加工需要。     

TiAlN涂层刀具对40CrNi钢干切削性能的影响

采用电弧离子镀在YT15硬质合金可转位车刀上沉积TiAlN涂层,用该涂层刀具对40CrNi钢进行干切削试验,并对切削过程中的切削力、切削温度、切屑形态进行了分析研究。结果表明:切削速度对切削温度的影响最大,其次是进给量和背吃刀量;随着切削用量的改变,切向力比轴向力、径向力的变化趋势更明显;长环形螺旋屑排屑顺畅,不易缠绕刀具,散热性好,是粗、精加工较理想的切屑形态;随着切削温度的升高,切屑颜色逐渐变为深蓝色。     

铸造不锈钢球头铣削力的实验研究

通过测力系统测量了铸造不锈钢倾斜平面球头铣削的铣削力,用线性回归方法得出了铣削力经验公式。分析了不同的铣削参数对铣削力的影响规律。其结果将对球头刀不锈钢铣前参数的优化选择有很大的参考价值。     

硬质合金材料及其涂层对不锈钢加工中刀具边界磨损的影响

硬质合金刀具在不锈钢加工中,其刀具耐用度主要是取决于后刀面边界磨损而不是主切削刃后刀面的平均磨损量。为了提高刀具耐用度,就必须减小后刀面边界磨损。本文对奥氏体不锈钢（ＳＵＳ３０４） 在车削及铣削加工中,采用Ｍ２０ 、Ｋ２０ 和Ｚ２０ 材料以及ＴｉＮ、Ｔｉ（Ｃ,Ｎ） 和（Ｔｉ,Ａｌ）Ｎ 物理涂层（ＰＶＤ）的硬质合金刀具进行了耐边界磨损的研究     

In-process estimation of radial immersion ratio in face milling using cutting force

In order to prevent tool breakage in milling, maximum total cutting force is regulated at a specific constant level, or threshold, through feed rate control. Since the threshold is a function of the immersion ratio, an estimation of the immersion ratio is necessary to flexibly determine the threshold. In this paper, a method of in-process estimation of the radial immersion ratio in face milling is presented. When an insert finishes sweeping, a sudden drop in cutting forces occurs. These force drops are equal to the cutting forces that act upon a single insert at the swept cutting angle and they can be acquired from cutting force signals in the feed and cross-feed directions. Average cutting forces per tooth period can also be calculated from the cutting force signals in two directions. The ratio of cutting forces acting upon a single insert at the swept angle of cut and the ratio of average cutting forces per tooth period are functions of the swept angle of cut and the ratio of radial to tangential cutting force. Using these parameters, the radial immersion ratio is estimated. Various experiments are performed to verify the proposed method. The results show that the radial immersion ratio can be estimated by this method regardless of other cutting conditions.Nomenclature F_T, F_R tangential and radial forces - F_X, F_Y cutting forces in feed direction and cross feed direction - dF_X, dF_Y cutting force differences before and after the immersion angle in X and Y direction - K_s specific cutting pressure - a depth of cut - r ratio between tangential force and radial force - s_t feed per tooth - instantaneous angle of cut - _s swept angle of cut - _T tooth spacing angle - w radial width of cut - R cutter radius - z number of inserts     

Modeling of cutting force under the tool flank wear effect in end milling Ti6Al4V with solid carbide tool

This paper presented a study of the relationship between cutting force and tool flank wear of solid carbide tool during the wet end milling Ti6Al4V. The modeling of 3D cutting force in end milling considering tool flank wear was discussed, which showed that for the given cutting conditions, tool geometries, and workpiece material, cutting force under the tool flank wear effect can be predicted easily and conveniently. In addition, the experimental work of end milling Ti6Al4V with solid carbide tool was developed to investigate the relationship between cutting force and tool flank wear, and comparison between experimental results and predicted results was discussed. The results showed that the proposed mathematical model can help to predict 3D cutting force under the tool flank wear effect with high accuracy.     

Experimental Study on Cutting Forces and Surface Integrity in High-Speed Side Milling of Ti-6Al-4V Titanium Alloy

This article is concerned with the cutting forces and surface integrity in high-speed side milling of Ti-6Al-4V titanium alloy. The experiments were conducted with coated carbide cutting tools under dry cutting conditions. The effects of cutting parameters on the cutting forces, tool wear and surface integrity (including surface roughness, microhardness and microstructure beneath the machined surface) were investigated. The velocity effects are focused on in the present study. The experimental results show that the cutting forces in three directions increase with cutting speed, feed per tooth and depth of cut (DoC). The widths of flank wear VB increases rapidly with the increasing cutting speed. The surface roughness initially decreases and presents a minimum value at the cutting speed 200 m/min, and then increases with the cutting speed. The microstructure beneath the machined surfaces had minimal or no obvious plastic deformation under the present milling conditions. Work hardening leads to an increment in micro-hardness on the top surface. Furthermore, the hardness of machined surface decreases with the increase of cutting speed and feed per tooth due to thermal softening effects. The results indicated that the cutting speed 200 m/min could be considered as a critical value at which both relatively low cutting forces and improved surface quality can be obtained.     

Influence of machining parameters on the machinability of particulate reinforced Al/SiC–MMC

The paper presents the result of an experimental investigation on the machinability of silicon carbide particulate aluminium metal matrix composite during turning using a rhombic uncoated carbide tool. The influence of machining parameters, e.g. cutting speed, feed and depth of cut on the cutting force has been investigated. The influence of the length of machining and cutting time on the tool wear and the influence of various machining parameters, e.g. cutting speed, feed, depth of cut on the surface finish criteria has been analyzed through the various graphical representations. The combined effect of cutting speed and feed on the flank wear has also been investigated. The influence of cutting speed, feed and depth of cut on the tool wears and built-up edge is analyzed graphically. The job surface condition and wear of the cutting tool edge for the different sets of experiments have been examined and compared for searching out the suitable cutting condition for effective machining performance during turning of Al/SiC-MMC. Test results show that no built-up edge is formed during machining of Al/SiC-MMC at high speed and low depth of cut. From the test results and different SEM micrographs, suitable range of cutting speed, feed and depth of cut can be selected for proper machining of Al/SiC-MMC.     

Prediction of cutting force, tool wear and surface roughness of Al6061/SiC composite for end milling operations using RSM

The results of mathematical modeling and the experimental investigation on the machinability of aluminium (Al6061) silicon carbide particulate (SiCp) metal matrix composite (MMC) during end milling process is analyzed. The machining was difficult to cut the material because of its hardness and wear resistance due to its abrasive nature of reinforcement element. The influence of machining parameters such as spindle speed, feed rate, depth of cut and nose radius on the cutting force has been investigated. The influence of the length of machining on the tool wear and the machining parameters on the surface finish criteria have been determined through the response surface methodology (RSM) prediction model. The prediction model is also used to determine the combined effect of machining parameters on the cutting force, tool wear and surface roughness. The results of the model were compared with the experimental results and found to be good agreement with them. The results of prediction model help in the selection of process parameters to reduce the cutting force, tool wear and surface roughness, which ensures quality of milling processes.     

硬质合金刀具车削Cr12Mn5Ni4Mo3Al不锈钢的试验研究

使用硬质合金刀具YW2进行Cr12Mn5Ni4Mo3Al不锈钢的干车削试验。分析了切削速度对车削力及表面粗糙度的影响,并采用扫描电子显微镜(SEM)观察刀具的磨损形貌。研究结果表明:使用硬质合金刀具YW2干车削Cr12Mn5Ni4Mo3Al不锈钢时,在小进给量和小背吃刀量切削的条件下,车削三向力的大小顺序为:径向力轴向力切向力;受积屑瘤的影响,表面粗糙度呈现出随车削速度的变化先减小后增大的变化趋势;硬质合金刀具后刀面磨损较轻微,而沿刀尖周围出现了较严重的粘结现象,前刀面上出现了较严重的划痕现象,低速时,前刀面还出现了贝壳状的剥落现象。     

TC11钛合金插铣工艺切削参数选择方法研究

为了优化TC11钛合金插铣加工的切削参数,采用三因素四水平正交实验法进行了插铣实验,建立了插铣过程中切削力和切削温度的经验公式,分析了插铣参数对切削力及切削参数的影响规律。基于此规律以及刀具许用挠度,提出了铣削速度、每齿进给量和铣削深度的选择方法。结果表明:铣削深度对切削力影响最大,而铣削速度对切削温度影响最大;插铣参数选取原则是在刀具材料允许下取较大铣削速度,适中的每齿进给量,最后根据刀具挠度选择合适的铣削深度。最后在根据此原则选择的插铣切削参数条件下,材料切除率达到了25.1 cm3/min。     

高速铣削铝合金时切削力和表面质量影响因素的试验研究

对高速铣削典型铝合金框架结构工件时的切削力和加工表面质量进行了试验研究。在高速进给铣削时 ,当进给方向发生改变 ,机床的加减速特性将导致在拐角处进给量减小、铣刀切入角增大 ,从而引起切削力增大和加工振动。在恒切削效率条件下高速铣削铝合金的试验结果表明 ,高速铣削时宜采用较小的轴向切深和较大的径向切深 ,以减小铣削力、提高加工表面质量 ;刀具动平衡偏心量是高速铣削时引起轴向振纹的主要原因     

高速铣削AF1410高强度钢的实验研究

高强度钢具有优异的机械性能和广阔的应用,但切削加工较为困难,存在加工效率低,加工表面质量差等问题.以AF1410高强度钢为研究对象,应用高速铣削的加工方法,使用涂层硬质合金刀片,对AF1410高强度钢进行了高速铣削实验,研究分析了在高速切削条件下刀具磨损、切削力、切削温度以及已加工表面粗糙度的变化规律.研究发现以TiC...